.all {
    width: 400px;
    height: 500px;
    border: 1px dotted grey;
    float: left;
    margin-left: 20px;
}

.person {
    width: 400px;
    height: 50px;
    line-height: 50px;
    text-align: center;
}

.contain {
    width: 400px;
    height: 350px;
}

#content {
    width: 99%;
    height: 100%;
    overflow-y: auto;
}

.footer {
    width: 100%;
    height: 100px;
    border: 1px solid green;
    display: flex;
    flex-direction: row;
    align-items: center;
}

.footer input {
    width: 70px;
    height: 50px;
    float: left;
    margin-right: 5px;
    margin-left: 5px;
    border-radius: 5%;
}

.footer button {
    width: 50px;
    height: 50px;
    float: left;
    background-color: deepskyblue;
    border-radius: 10%;
    margin-right: 5px;
}

.footer textarea {
    width: 200px;
    height: 80px;
    overflow-y: scroll;
    float: left;
    margin-right: 5px;
    border-radius: 5%;
}


/*在线用户的列表*/

.all2 {
    width: 150px;
    height: 500px;
    border: 1px dotted green;
    float: left;
}

.title {
    width: 150px;
    height: 50px;
    line-height: 50px;
    background-color: bisque;
}

.userList {
    overflow-y: scroll;
    height: 450px;
}